2 Safety2.1 Safety SymbolsThe following symbols are used in this guide:WARNINGIndicates a potentially hazardous situation that couldresult in death or serious injury.CAUTIONIndicates a potentially hazardous situation that couldresult in minor or moderate injury. It can also be used toalert against unsafe practices.NOTICEIndicates important information, including situations thatcan result in damage to equipment or property.2.2 Qualified PersonnelCorrect and reliable transport, storage, installation,operation, and maintenance are required for the trouble-free and safe operation of the frequency converter. Onlyqualified personnel are allowed to install and operate thisequipment.Qualified personnel are defined as trained staff, who areauthorized to install, commission, and maintain equipment,systems, and circuits in accordance with pertinent laws andregulations. Also, the qualified personnel must be familiarwith the instructions and safety measures described in thismanual.2.3 Safety PrecautionsWARNINGHIGH VOLTAGEFrequency converters contain high voltage whenconnected to AC mains input, DC supply, or load sharing.Failure to perform installation, start-up, and maintenanceby qualified personnel can result in death or seriousinjury.• Only qualified personnel must perform instal-lation, start-up, and maintenance.• Before performing any service or repair work,use an appropriate voltage measuring device tomake sure that there is no remaining voltage onthe frequency converter.WARNINGUNINTENDED STARTWhen the frequency converter is connected to AC mains,DC supply, or load sharing, the motor may start at anytime. Unintended start during programming, service, orrepair work can result in death, serious injury, orproperty damage. The motor can start via an externalswitch, a fieldbus command, an input reference signalfrom the LCP, or after a cleared fault condition.To prevent unintended motor start:• Disconnect the frequency converter from themains.• Press [Off/Reset] on the LCP beforeprogramming parameters.• Completely wire and assemble the frequencyconverter, motor, and any driven equipmentbefore connecting the frequency converter toAC mains, DC supply, or load sharing.WARNINGDISCHARGE TIMEThe frequency converter contains DC-link capacitors,which can remain charged even when the frequencyconverter is not powered. High voltage can be presenteven when the warning LED indicator lights are off.Failure to wait the specified time after power has beenremoved before performing service or repair work canresult in death or serious injury.• Stop the motor.• Disconnect AC mains and remote DC-link powersupplies, including battery back-ups, UPS, andDC-link connections to other frequencyconverters.• Disconnect or lock PM motor.• Wait for the capacitors to discharge fully. Theminimum waiting time is specified in Table 2.1and is also visible on the product label on topof the frequency converter.• Before performing any service or repair work,use an appropriate voltage measuring device tomake sure that the capacitors are fullydischarged.Safety VLT® AutomationDrive FC 301/3026 Danfoss A/S © 05/2018 All rights reserved. MG33AT0222